#include "obstack.h"
/* cleanup_cfg maintains following flags for each basic block. */
-enum bb_flags {
+
+enum bb_flags
+{
/* Set if life info needs to be recomputed for given BB. */
BB_UPDATE_LIFE = 1,
/* Set if BB is the forwarder block to avoid too many
forwarder_block_p calls. */
BB_FORWARDER_BLOCK = 2
- };
+};
-#define BB_FLAGS(bb) (enum bb_flags)(bb)->aux
-#define BB_SET_FLAG(bb,flag) \
- (bb)->aux = (void *) (long) ((enum bb_flags)(bb)->aux | (flag))
-#define BB_CLEAR_FLAG(bb,flag) \
- (bb)->aux = (void *) (long) ((enum bb_flags)(bb)->aux & ~(flag))
+#define BB_FLAGS(BB) (enum bb_flags) (BB)->aux
+#define BB_SET_FLAG(BB, FLAG) \
+ (BB)->aux = (void *) (long) ((enum bb_flags) (BB)->aux | (FLAG))
+#define BB_CLEAR_FLAG(BB, FLAG) \
+ (BB)->aux = (void *) (long) ((enum bb_flags) (BB)->aux & ~(FLAG))
-#define FORWARDER_BLOCK_P(bb) (BB_FLAGS(bb) & BB_FORWARDER_BLOCK)
+#define FORWARDER_BLOCK_P(BB) (BB_FLAGS (BB) & BB_FORWARDER_BLOCK)
static bool try_crossjump_to_edge PARAMS ((int, edge, edge));
static bool try_crossjump_bb PARAMS ((int, basic_block));
{
if (!bb)
return;
+
BB_SET_FLAG (bb, BB_UPDATE_LIFE);
if (forwarder_block_p (bb))
BB_SET_FLAG (bb, BB_FORWARDER_BLOCK);
\f
/* Attempt to prove that operation is NOOP using CSElib or mark the effect
on register. Used by jump threading. */
+
static bool
mark_effect (exp, nonequal)
rtx exp;
if (REG_P (XEXP (exp, 0)))
CLEAR_REGNO_REG_SET (nonequal, REGNO (XEXP (exp, 0)));
return false;
+
case SET:
if (rtx_equal_for_cselib_p (SET_DEST (exp), SET_SRC (exp)))
return false;
return true;
SET_REGNO_REG_SET (nonequal, REGNO (SET_SRC (exp)));
return false;
+
default:
return false;
}
nonequal = BITMAP_XMALLOC();
CLEAR_REG_SET (nonequal);
+
/* Now assume that we've continued by the edge E to B and continue
processing as if it were same basic block.
-
Our goal is to prove that whole block is an NOOP. */
+
for (insn = NEXT_INSN (b->head); insn != b->end && !failed;
insn = NEXT_INSN (insn))
{
else
failed |= mark_effect (pat, nonequal);
}
+
cselib_process_insn (insn);
}
bool changed = false;
edge e, next, threaded_edge;
- for (e = b->succ; e ; e = next)
+ for (e = b->succ; e; e = next)
{
basic_block target, first;
int counter;
counter = n_basic_blocks;
new_target = target->succ->dest;
}
+
/* Allow to thread only over one edge at time to simplify updating
of probabilities. */
else if ((mode & CLEANUP_THREADING) && !threaded)
new_target_threaded = true;
}
}
+
if (!new_target)
break;
if (GET_CODE (insn) != NOTE)
insn = NEXT_INSN (insn);
- for (;insn && GET_CODE (insn) != CODE_LABEL && !INSN_P (insn);
+ for (; insn && GET_CODE (insn) != CODE_LABEL && !INSN_P (insn);
insn = NEXT_INSN (insn))
if (GET_CODE (insn) == NOTE
&& NOTE_LINE_NUMBER (insn) == NOTE_INSN_LOOP_BEG)
if (GET_CODE (insn) == NOTE)
break;
}
+
counter++;
target = new_target;
threaded |= new_target_threaded;
else if (!redirect_edge_and_branch (e, target))
{
if (rtl_dump_file)
- fprintf (rtl_dump_file, "Forwarding edge %i->%i to %i failed.\n",
+ fprintf (rtl_dump_file,
+ "Forwarding edge %i->%i to %i failed.\n",
b->index, e->dest->index, target->index);
continue;
}
+
/* We successfully forwarded the edge. Now update profile
data: for each edge we traversed in the chain, remove
the original edge's execution count. */
do
{
edge t;
+
first->count -= edge_count;
first->succ->count -= edge_count;
first->frequency -= edge_frequency;
t = threaded_edge;
else
t = first->succ;
+
first = t->dest;
}
while (first != target);
BB_SET_FLAG (a, BB_UPDATE_LIFE);
if (rtl_dump_file)
- {
- fprintf (rtl_dump_file, "Moved block %d before %d and merged.\n",
- a->index, b->index);
- }
+ fprintf (rtl_dump_file, "Moved block %d before %d and merged.\n",
+ a->index, b->index);
/* Swap the records for the two blocks around. Although we are deleting B,
A is now where B was and we want to compact the BB array from where
BB_SET_FLAG (a, BB_UPDATE_LIFE);
if (rtl_dump_file)
- {
- fprintf (rtl_dump_file, "Moved block %d after %d and merged.\n",
- b->index, a->index);
- }
+ fprintf (rtl_dump_file, "Moved block %d after %d and merged.\n",
+ b->index, a->index);
}
/* Attempt to merge basic blocks that are potentially non-adjacent.
update_forwarder_flag (b);
if (rtl_dump_file)
- {
- fprintf (rtl_dump_file, "Merged %d and %d without moving.\n",
- b->index, c->index);
- }
+ fprintf (rtl_dump_file, "Merged %d and %d without moving.\n",
+ b->index, c->index);
return true;
}
+
/* Otherwise we will need to move code around. Do that only if expensive
transformations are allowed. */
else if (mode & CLEANUP_EXPENSIVE)
for (tmp_edge = c->succ; tmp_edge; tmp_edge = tmp_edge->succ_next)
if (tmp_edge->flags & EDGE_FALLTHRU)
break;
+
c_has_outgoing_fallthru = (tmp_edge != NULL);
for (tmp_edge = b->pred; tmp_edge; tmp_edge = tmp_edge->pred_next)
if (tmp_edge->flags & EDGE_FALLTHRU)
break;
+
b_has_incoming_fallthru = (tmp_edge != NULL);
b_fallthru_edge = tmp_edge;
if (b_has_incoming_fallthru)
{
basic_block bb;
+
if (b_fallthru_edge->src == ENTRY_BLOCK_PTR)
return false;
bb = force_nonfallthru (b_fallthru_edge);
else
BB_SET_FLAG (b_fallthru_edge->src, BB_UPDATE_LIFE);
}
+
merge_blocks_move_predecessor_nojumps (b, c);
return true;
}
+
return false;
}
\f
return true;
}
}
+
return false;
}
+
return true;
}
\f
last1 = i1;
i1 = PREV_INSN (i1);
}
+
i2 = bb2->end;
if (onlyjump_p (i2)
|| (returnjump_p (i2) && !side_effects_p (PATTERN (i2))))
/* Ignore notes. */
while (!active_insn_p (i1) && i1 != bb1->head)
i1 = PREV_INSN (i1);
+
while (!active_insn_p (i2) && i2 != bb2->head)
i2 = PREV_INSN (i2);
last1 = i1, last2 = i2;
ninsns++;
}
+
i1 = PREV_INSN (i1);
i2 = PREV_INSN (i2);
}
#ifdef HAVE_cc0
- if (ninsns)
- {
- /* Don't allow the insn after a compare to be shared by
- cross-jumping unless the compare is also shared. */
- if (reg_mentioned_p (cc0_rtx, last1) && ! sets_cc0_p (last1))
- last1 = afterlast1, last2 = afterlast2, ninsns--;
- }
+ /* Don't allow the insn after a compare to be shared by
+ cross-jumping unless the compare is also shared. */
+ if (ninsns && reg_mentioned_p (cc0_rtx, last1) && ! sets_cc0_p (last1))
+ last1 = afterlast1, last2 = afterlast2, ninsns--;
#endif
/* Include preceding notes and labels in the cross-jump. One,
{
while (last1 != bb1->head && !active_insn_p (PREV_INSN (last1)))
last1 = PREV_INSN (last1);
+
if (last1 != bb1->head && GET_CODE (PREV_INSN (last1)) == CODE_LABEL)
last1 = PREV_INSN (last1);
+
while (last2 != bb2->head && !active_insn_p (PREV_INSN (last2)))
last2 = PREV_INSN (last2);
+
if (last2 != bb2->head && GET_CODE (PREV_INSN (last2)) == CODE_LABEL)
last2 = PREV_INSN (last2);
unconditional jump, or a fake edge to exit. */
if (bb1->succ && !bb1->succ->succ_next
&& !(bb1->succ->flags & (EDGE_COMPLEX | EDGE_FAKE)))
- {
- if (! bb2->succ || bb2->succ->succ_next
- || (bb2->succ->flags & (EDGE_COMPLEX | EDGE_FAKE)))
- return false;
- return true;
- }
+ return (bb2->succ && !bb2->succ->succ_next
+ && (bb2->succ->flags & (EDGE_COMPLEX | EDGE_FAKE)) == 0);
/* Match conditional jumps - this may get tricky when fallthru and branch
edges are crossed. */
should be optimized out already. */
if (FORWARDER_BLOCK_P (f1->dest))
f1 = f1->dest->succ;
+
if (FORWARDER_BLOCK_P (f2->dest))
f2 = f2->dest->succ;
code2 = reversed_comparison_code (cond2, bb2->end);
else
code2 = GET_CODE (cond2);
+
if (code2 == UNKNOWN)
return false;
{
rtx note1, note2;
int prob1, prob2;
+
note1 = find_reg_note (bb1->end, REG_BR_PROB, 0);
note2 = find_reg_note (bb2->end, REG_BR_PROB, 0);
if (abs (prob1 - prob2) > REG_BR_PROB_BASE / 20)
return false;
}
+
else if (note1 || note2)
return false;
}
{
if (e1->flags & EDGE_EH)
nehedges1++;
+
if (e2->flags & EDGE_EH)
nehedges2++;
+
if (e1->flags & EDGE_FALLTHRU)
fallthru1 = e1;
if (e2->flags & EDGE_FALLTHRU)
fallthru2 = e2;
}
+
/* If number of edges of various types does not match, fail. */
- if (e1 || e2)
- return false;
- if (nehedges1 != nehedges2)
- return false;
- if ((fallthru1 != 0) != (fallthru2 != 0))
+ if (e1 || e2
+ || nehedges1 != nehedges2
+ || (fallthru1 != 0) != (fallthru2 != 0))
return false;
/* fallthru edges must be forwarded to the same destination. */
? fallthru1->dest->succ->dest: fallthru1->dest);
basic_block d2 = (forwarder_block_p (fallthru2->dest)
? fallthru2->dest->succ->dest: fallthru2->dest);
+
if (d1 != d2)
return false;
}
+
/* In case we do have EH edges, ensure we are in the same region. */
if (nehedges1)
{
rtx n1 = find_reg_note (bb1->end, REG_EH_REGION, 0);
rtx n2 = find_reg_note (bb2->end, REG_EH_REGION, 0);
+
if (XEXP (n1, 0) != XEXP (n2, 0))
return false;
}
+
/* We don't need to match the rest of edges as above checks should be enought
to ensure that they are equivalent. */
return true;
if (src1->pred
&& !src1->pred->pred_next
&& FORWARDER_BLOCK_P (src1))
- {
- e1 = src1->pred;
- src1 = e1->src;
- }
+ e1 = src1->pred, src1 = e1->src;
+
if (src2->pred
&& !src2->pred->pred_next
&& FORWARDER_BLOCK_P (src2))
- {
- e2 = src2->pred;
- src2 = e2->src;
- }
+ e2 = src2->pred, src2 = e2->src;
/* Nothing to do if we reach ENTRY, or a common source block. */
if (src1 == ENTRY_BLOCK_PTR || src2 == ENTRY_BLOCK_PTR)
if (FORWARDER_BLOCK_P (e1->dest)
&& FORWARDER_BLOCK_P (e1->dest->succ->dest))
return false;
+
if (FORWARDER_BLOCK_P (e2->dest)
&& FORWARDER_BLOCK_P (e2->dest->succ->dest))
return false;
if (FORWARDER_BLOCK_P (d))
d = d->succ->dest;
+
for (s2 = src1->succ; ; s2 = s2->succ_next)
{
basic_block d2 = s2->dest;
if (d == d2)
break;
}
+
s->count += s2->count;
/* Take care to update possible forwarder blocks. We verified
s->dest->count += s2->count;
s->dest->frequency += EDGE_FREQUENCY (s);
}
+
if (FORWARDER_BLOCK_P (s2->dest))
{
s2->dest->succ->count -= s2->count;
s2->dest->count -= s2->count;
s2->dest->frequency -= EDGE_FREQUENCY (s);
}
+
if (!redirect_to->frequency && !src1->frequency)
s->probability = (s->probability + s2->probability) / 2;
else
- s->probability =
- ((s->probability * redirect_to->frequency +
- s2->probability * src1->frequency)
- / (redirect_to->frequency + src1->frequency));
+ s->probability
+ = ((s->probability * redirect_to->frequency +
+ s2->probability * src1->frequency)
+ / (redirect_to->frequency + src1->frequency));
}
note = find_reg_note (redirect_to->end, REG_BR_PROB, 0);
/* Skip possible basic block header. */
if (GET_CODE (newpos1) == CODE_LABEL)
newpos1 = NEXT_INSN (newpos1);
+
if (GET_CODE (newpos1) == NOTE)
newpos1 = NEXT_INSN (newpos1);
last = src1->end;
/* Attempt to merge blocks as made possible by edge removal. If a block
has only one successor, and the successor has only one predecessor,
they may be combined. */
-
do
{
changed = false;
c = BASIC_BLOCK (b->index - 1);
if (rtl_dump_file)
fprintf (rtl_dump_file, "Deleting block %i.\n", b->index);
+
flow_delete_block (b);
changed = true;
b = c;
|| ! label_is_jump_target_p (b->head, b->pred->src->end)))
{
rtx label = b->head;
+
b->head = NEXT_INSN (b->head);
delete_insn_chain (label, label);
if (rtl_dump_file)
if (rtl_dump_file)
fprintf (rtl_dump_file, "Deleting fallthru block %i.\n",
b->index);
+
c = BASIC_BLOCK (b->index ? b->index - 1 : 1);
redirect_edge_succ_nodup (b->pred, b->succ->dest);
flow_delete_block (b);
if ((mode & CLEANUP_UPDATE_LIFE) && changed_overall)
{
bool found = 0;
+
blocks = sbitmap_alloc (n_basic_blocks);
sbitmap_zero (blocks);
for (i = 0; i < n_basic_blocks; i++)
found = 1;
SET_BIT (blocks, i);
}
+
if (found)
update_life_info (blocks, UPDATE_LIFE_GLOBAL,
PROP_DEATH_NOTES | PROP_SCAN_DEAD_CODE
| PROP_KILL_DEAD_CODE);
sbitmap_free (blocks);
}
+
for (i = 0; i < n_basic_blocks; i++)
BASIC_BLOCK (i)->aux = NULL;
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